Molecular Phylogeny of Anabaena circinalis and Its Identification in Environmental Samples by PCR

Although the cyanobacterium Anabaena circinalis occurs worldwide, Australian isolates are believed to exclusively possess the saxitoxin group neurotoxins (paralytic shellfish poisons). Identification of A. circinalis in a mixed population is complicated due to limited morphological differences between Anabaena species. Sequence analysis of the DNA-dependent RNA polymerase (rpoC1) gene from 24 Anabaena isolates, including 12 designated A. circinalis, permitted a phylogenetic analysis to be performed. In addition, an A. circinalis-specific PCR was developed and tested successfully on environmental samples.